1. Field
The present disclosure relates to an accelerator pedal apparatus applied to vehicles and the like having a drive-by-wire system, and in particular, relates to an accelerator pedal apparatus including a reaction force generating mechanism which generates reaction force (i.e. push-back force) against pedaling force of a pedal arm for danger avoidance, danger notification or the like.
2. Description of the Related Art
For an engine mounted on an automobile and the like, an accelerator pedal apparatus including a hysteresis generating mechanism to provide a hysteresis characteristic to relation between a stroke (i.e., a depression amount) and pedaling force of an accelerator pedal as pedaling force during return operation which is smaller than pedaling force during depression operation is applied to an electronically controlled throttle system (i.e., a drive-by-wire system). In the above structure, an accelerator pedal apparatus including pedaling force change means (i.e., a reaction force adding mechanism) is known which appropriately adds reaction force to pedaling force at the depression side of the accelerator pedal to obtain appropriate pedaling force in accordance with vehicle drive states while maintaining an initially-set characteristic pedaling force at the return side of the accelerator pedal regardless of the vehicle drive states. For example, see Japanese Laid-open Patent Publication No. 2004-314871.
Examples of situations to suppress depression by adding reaction force during depression operation of an accelerator pedal include a situation to improve fuel consumption by suppressing excessive depression, a situation to notify a driver that they are getting close to a vehicle in front of them during driving, and a situation to avoid or notify a driver of other danger.
The above situations are not limited only to a time during a depression operation of the accelerator pedal. Even during return operation of the accelerator pedal, there is a danger of getting too close to a vehicle in front of a driver or that smooth driving cannot be performed when the return amount is insufficient or the return operation is slow.